Caffeine is the most commonly used drug in the world. In moderate doses (75-150 mg), it elevates neural activity in many parts of the brain, postpones fatigue, and enhances performance of simple intellectual tasks and physical work that involves endurance. The most common therapeutic use of caffeine is to relieve pain, especially headache pain, although it is also a mild diuretic and a respiratory stimulant.
Typically, caffeine is administered either orally or intravenously. These delivery methods have a number of limitations. Peak plasma concentrations following oral administration are generally not reached until 50 to 75 minutes. Intravenous injection, while rapidly delivering the drug, involves the discomfort and risk of infection associated with catheterization or injection.
It is desirable to provide a new route of administration for caffeine that allows for the rapid acquisition of peak plasma concentrations without the disadvantages of catheterization or injection. The provision of such a route is an object of the present invention.